Chandigarh, July 11 -- As part of an intensified checking drive, the Chandigarh police on the intervening night of Wednesday and Thursday organised a special 'Operation Seal'. A total of 62 internal barriers and 18 outer border nakas were set up. As many as 641 vehicles were checked during the operation and around 23 challans were issued under various categories. Police have also impounded four vehicles. During this operation, around 50 PCR vehicles and Cheetha Motorcycles patrolled in the city. All SDPOs, SHOs, and in-charge of police posts (I/CPPs), along with approximately 320 NGO/ORs, were deployed for this special drive....